Molybdomenite is a rare lead selenite mineral typically found as a secondary mineral in oxidized selenium-rich ore deposits. It is known for forming delicate, pearly-lustered platy or tabular crystals that are often difficult for collectors to acquire.
Is this molybdomenite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch molybdomenite with a known reference. Molybdomenite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: pearly, adamantine, to greasy.
- 4Match the color rangeCompare against the expected color range: colorless, yellowish white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: bladed.
Often confused with
Molybdomenite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads pearly, adamantine, to greasy on Molybdomenite and adamantine, resinous to vitreous on Anglesite.
How to tell apart: Luster reads pearly, adamantine, to greasy on Molybdomenite and adamantine, tending toward vitreous, resinous on Cerussite.
Often found alongside molybdomenite
Minerals reported to co-occur with molybdomenite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- PbSeO₃
- Mohs hardness
- 3.5
- Density
- 7.07 g/cm³
- Colors
- Streak
- White
- Luster
- Pearly, adamantine, to greasy
- Transparency
- Transparent to translucent
- Crystal system
- Monoclinic
- Crystal habit
- Bladed
- Cleavage
- Good on {001}; fair on {h0l}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare species in the oxidized zone of selenium-bearing hydrothermal base metal deposits
Where rockhounds find molybdomenite
Classic worldwide localities
- Bozo #1 mine, Skull Creek, Moffat Co., Colorado, USA
- Cerro de Cacheuta, Mendoza Province, Argentina
- Pacajake mine, Hiaco, 24 km east-northeast of Colquechaca, and the El Dragón mine, 30 km southwest of Cerro Rico de Potosí, Potosí, Bolivia
- Trogtal quarry, near Lautenthal, Harz Mountains, Germany
- Tolbachik fissure volcano, Kamchatka Peninsula, Russia
- Ranwick uranium mine, north of Sault Sainte Marie, Ontario, Canada
Field-hunting tip
Where it forms: A rare species in the oxidized zone of selenium-bearing hydrothermal base metal deposits. If you start seeing chalcomenite, clausthalite, uraninite in float, you are in the right ground. Typical habit: bladed. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify molybdomenite?+
Where is molybdomenite found?+
Is molybdomenite safe to handle?+
What rocks look like molybdomenite?+
What minerals are found with molybdomenite?+
What kind of rock does molybdomenite form in?+
What is molybdomenite used for?+
Find molybdomenite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
